When designing and structuring light and compact optical systems, for manufacturing purposes it is above all the stability of the image properties which is a highly essential quality criterion, alongside the adjustment precision that can be achieved. As well as sufficient mechanical stability, such systems must also be as resilient as possible against changes to the operating conditions. In particular, thermal influences when a temperature change occurs can present a challenge. Due to thermal expansion and the thermo-optical effect, the geometric and optical properties of an image system are frequently highly dependent on temperature, so that a number of corresponding countermeasures must be taken to offset them.
An additional problem is that particularly compact optical image systems are today in many cases manufactured from optical synthetic materials or polymers, such as PMMA, COC, COP or PC, due to their lower weight and the significantly reduced manufacturing costs. These materials have comparatively high thermal expansion coefficients as opposed to the conventional optical glasses used to date, and expand by around two decimal powers more when there is a temperature increase than conventional quartz glass, for example. The thermal expansion coefficient α of optical polymers is approximately in the range between 0.1·10−4 K−1 and 0.85·10−4 K−1 (in comparison: quartz glass 0.54 10−6 K−1). Furthermore, with these materials, the optical properties are strongly temperature-dependent due to the thermo-optical coefficients β, so that alongside a change in length or distance, a refractive index change to the materials must also be taken into account. It is furthermore known that with optical polymers, there is even a direct linear connection between their thermal longitudinal expansion behaviour and the thermal refractive index change to the materials that occurs (Zhang et al., Polymer 47 (2006) 4893-4896).
Synthetic lenses in particular have the property of having a high degree of influence on the focus drift of an image due to a strong refraction index change to the material when the temperature is changed. In multi-lens systems according to the prior art, the focus drift is frequently offset through the use of lenses made of synthetic material which have a positive and a negative refraction index. With simple optics with just one single lens, such as those used e.g. for the collimation of laser diodes, this is often not possible. The conventional constructive use of just one single synthetic lens is, in relation to the focus drift that occurs, not suitable for maintaining the necessary image performance (spot diameter). Compensation by frame materials with a high expansion coefficient can often also not be applied, since as a result, the space needed and the weight of the image optics usually increases considerably.
The object of the invention is thus to provide an arrangement for supporting an optical component, which can for example be a lens, a window, a mirror, a beam splitter, a wave plate, a filter or a non-linear crystal, and an optical system that comprises this arrangement, which avoids one or more of the problems of the prior art described when constructing compact optical systems, or at least considerably reduces them. In particular, an arrangement for supporting a synthetic lens on a carrier (also described as a frame or retainer) is required, in which image errors of the lens which occur when the temperature changes can be compensated within an image system without additional space requirements or an increase in weight, and in which the focus drift which is generated by a refraction index change can better be compensated than through the use of a material with a high expansion coefficient between the laser diode and the lens.